TCP IP Illustrated

5555 sun1305 ack 6147 win 2048 bsdi5555 sun1305

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: 4) . ack 1 win 4096 urg . ack 1 win 4096 urg . ack 1 win 4096 urg . ack 1 win 4096 urg . ack 1 win 4096 urg bsdi.5555 > sun.1305: . ack 4097 win 0 sun.1305 > bsdi.5555: . ack 1 win 4096 urg 4098 bsdi.5555 > sun.1305: . ack 4097 win 2048 sun.1305 > bsdi.5555: . 4097:5121(1024) ack 1 win 4096 urg 4098 sun.1305 > bsdi.5555: . 5121:6145(1024) ack 1 win 4096 bsdi.5555 > sun.1305: . ack 4097 win 4096 file:///D|/Documents%20and%20Settings/bigini/Docu...homenet2run/tcpip/tcp-ip-illustrated/tcp_bulk.htm (21 of 24) [12/09/2001 14.47.22] Chapter 20. TCP Bulk Data Flow 9.835913 (0.0008) 9.840264 18 (0.0044) 9.842386 19 (0.0021) 9.843622 20 (0.0012) 9.844320 21 (0.0007) 17 sun.1305 > bsdi.5555: FP 6145:6146(1) ack 1 win 4096 bsdi.5555 > sun.1305: . ack 6147 win 2048 bsdi.5555 > sun.1305: . ack 6147 win 4096 bsdi.5555 > sun.1305: F 1:1(0) ack 6147 win 4096 sun.1305 > bsdi.5555: . ack 2 win 4096 Figure 20.14 tcpdump output for TCP urgent mode. After the fourth application write of normal data, the application writes 1 byte of data and enters urgent mode. Line 6 is the result of this application write. The urgent pointer is set to 4098. The urgent pointer is sent with the URG flag even though the sender cannot send any data. Five of these ACKs are sent in about 13 ms (lines 6-10). The first is sent when the application writes 1 byte and enters urgent mode. The next two are sent when the application does the final two writes of 1024 bytes. (Even though TCP can't send these 2048 bytes of data, each time the application performs a write, the TCP output function is called, and when it sees that urgent mode has been entered, sends another urgent notification.) The fourth of these ACKs occurs when the application closes its end of the connection. (The TCP output function is again called.) The sending application terminates milliseconds after it startsbefore the receiving application has issued its first write. TCP queues all the data and sends it when it can. (...
View Full Document

This test prep was uploaded on 04/04/2014 for the course ECE EL5373 taught by Professor Guoyang during the Spring '12 term at NYU Poly.

Ask a homework question - tutors are online